Autoclave and the like



Oct ,28, 194i- Y J. F. GscHwlN'D AUTOCLVE AND THE LIKE Filed May 18, 1939 Avlam-QR law e e ATTORNEYS Patented Oct. 28, 194

UNITED STATES' PATENT. FFICE 2,260,710" Y 7. Y f

e AU'rocL'AvE AND THE una Jean F. Gschwind, Mount Vernon,N. Y. Y Applicaticn May 1s, 1939, serum. 274,389', j, f

3 claims. (o1. 234-290) ,'I'his invention relates to vulcanizers, autoclaves and the like, and ,more especially to the arrangement of means for supplying heat ,to articles within such devices.

I-Ieretofore it has been customary to heat autoclaves or other similar closed chambers by in-L troducing live steam directly into such chamber. The steam is condensed while giving up heat to the treated goods and to the autoclave itself. However, in manycases the condensate is contaminatedand cannot be returned to the boiler and, therefore, in most installations, as for instance, in rubber plants, the condensate is not reclaimed but is disposed of in any suitable manner. This procedure entails a number of disadvantages such, for example, yas loss of heat, loss of condensate and the necessity of steadily venting the autoclave in order to eliminate air and gases introduced with thesteam. Thecontinuous venting during the entiresteaming operation is another source of steam loss, as it is diiicult kto separate air or gases from steam. Furthermore, if the steam is throttled from a higher to a lower pressure, the steam becomes superheated which generally is another undesirable feature.

In order to overcome the disadvantages of direct steam supply, indirect heating means are sometimes used and heating jackets or coils are provided in the lower part of the autoclave. Some water previously introduced into the steam space is evaporated when the heat is turned on. The heating surfaces are usually so arranged that any condensate produced will eventually touch such surfaces, thereby assuring evaporation of the liquid and the lling of the autoclave with steam.

The heating cycles of autoclaves and the like are usually composed of two parts, a. the heating up period and b the curing period at a predetermined temperature. The indirect heating surfaces have to be dimensioned to satisfy the greatest heat demand in a given time which occurs during the heating up period. Experience shows, however, that the exclusive use of such indirect heating means is often not practicable because of excessive equipment cost, limited space for coils or jackets or a high pressure involved.

An object of this invention is the combination and the particular arrangement of direct and indirect heat sources in autoclaves to assure a quick heating up and a minimum of the heat and condensate losses. In particular, this invening the second part ,of the operationnknown as the curing period in as much as there'is n o necessity of addingheating ymedium `into the curing chamber during thistimeV Y, n e

Y, Other objects, novel -features and advantages of-this invention willbe apparent from the -followingvspeciflcation and accompanying drawing, wherein-, n Figure 1 is .a verticalesection through onenform of vautoclave embodying the invention;, i? Y Figure 2 is a vertical section througha second form'of autoclave; f'

Figurer 3 isa verticalsectiondthroughwathird e form of autoclave; and ,j

A Figure 4 is va sectionV on In Figure 1 isv illustrated atypical autoclave comprising a body I0 having a removable cover II andy la false 4f bottom lor. perforated shelf lf2v on which the goodsto lbe steam treated are ,sup-- ported .A 'pipe 13, is Provided .forv introducing. steaminto thetop of the autoclave and the pipe is provided with a control valve I4 and a check valve I5. A pressure gauge I6 or thermometer is provided on the lid or cover II and likewise an air vent II is supported by such cover.

In the bottom of the chamber is provided a coil I8, the inlet and outlet of which are provided with control valves I9 and 20. An outlet pipe 2I leads from the chamber I0 below the false bottom I2 and above the coil I8 and is equipped the me, 41-4 ifA sgiwith a steam trap 22 which prevents any evacuation of vapor, but acts as an overflow for condensate to maintain a body of liquid in the chamber I0 having its level below the false bottom I2 and above the coil I8.

When the autoclave has been properly loaded and closed, heating medium is supplied to the coil IB by opening the valves I9 and 20 and live steam is admitted through the pipe I3 by opening the valve I4.' The resulting indirect and direct heating action assures a quick rise in pressure and temperature within the chamber. The condensate formed iiows to the bottom of the vessel where it is re-.evaporated by contact with the coil I8. As soon as the heating up period is finished and the desired temperature or pressure is reached, the valve I4 isclosed and the curing period begins. Up until this time the vent I1 advantageously is kept open in order to eliminate all air and gases, However, during the curing period the vent should be kept closed yas no more air will be introduced into the chamber. With proper dimensioning of the heating coil the tion prevents the loss of any heating ud durcuring temperature will be maintained and there tom of the chamber after each run to supply the 1 liquid necessary for the subsequent run.

In the modication disclosed in Figure 24 the coil I8 is omitted and in placey thereof there is provided a jacket 23 to which steam is supplied Such means is through the pipe 24 and condensate isr removed through the pipe 25. The remainder of the autoclave is of the same construction as shown in Figure 1 and its operation is the same as that of Figurel.

In the modification illustrated in Figure 3 the autoclave 30 is horizontal and is provided with the removable end 3l. The goods to be treated are supported by a carriage (not shown) having wheels which run on the tracks 32. In this modication a coil I8 is arranged in the lowest part of the vessel and in such way as not to interfere with the carriage. chamber is provideda barrier or dam 33 tightly attached to the outer shell so as to prevent the escape of liquid through the open end of the autoclave. The chamber of this modication is provided with a gauge IB, vent I'I, steam inlet I4, and condensate outlet 2 I, the same as in-l the previous modiiications. l

The operation of the apparatus disclosed in Figures 3 and 4 is the same as that of the previous modifications, except that the goods to be treated are introduced into and removed from the chamber 33 while being supported by a car- At the open end of the riage. Indirect heat is supplied by the coil I8 and live steam is supplied through the pipe I4.

Iclaim:

1. In a device of the character described, a closed chamber, a steam inlet in its upper portion, reticulated article supporting means spaced from the bottom of said chamber, an outlet leading from said chamber above the bottom thereof and below said supporting means, a steam trap in said outlet permitting escape of excess condensate and maintaining a body of condensate in the chamber having its level belowsaid supporting means, and means for supplying indirect heat to liquid in the bottom of said chamber.

2. In a device of the character described, a closed chamber, a steam inlet in its upper portion, reticulated article supporting means spaced from Vthe bottom of said chamber, a coil in said chamber below said supporting means, means for supplying heating medium to said coil, and an outlet leadingv from said chamber above said coil and below said supporting means, and a steam trap in said outlet permitting escape of excess condensate and automatically maintaining a body of condensate in the chamber having its level below saidsupporting means and above said coil.

3. In a device of the character described, a horizontal cylindrical chamberl open at one end, a cover therefor, horizontal tracks in said chamber for an article supporting carriage, a baille across the open end of said cylinder below said tracks, an outlet leading from said chamber above the bottom thereof and bel-ow said tracks, a steam trap in said outlet permitting escape of excess condensate and maintaining a body of condensate in the chamber having its level below said Supporting means, means for supplying indirect heat to liquid in the bottom of said chamber, and means for supplying steam to the upper portion of said chamber.

v JEAN F. GSCHWIN'D. 

